JP6031194B2 - Aluminum composite material and method for producing aluminum composite material - Google Patents

Description

  The present invention relates to an aluminum composite material and a method for producing the aluminum composite material.

  As materials having neutron absorption performance, alloys disclosed in Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4 are known.

JP-A-62-177141 JP-A-62-243733 JP-A 63-038553 US Pat. No. 7,625,520

  When manufacturing aluminum composites with neutron absorption performance used for radioactive materials storage containers, etc., if the aluminum composites do not have properties (workability) suitable for manufacturing articles, It cannot be manufactured and the performance of the article may be reduced.

  An object of an aspect of the present invention is to provide an aluminum composite material having neutron absorption performance and good workability, and a method for producing the aluminum composite material.

  An aluminum composite material according to an aspect of the present invention includes a first metal plate, a second metal plate, a base material disposed between the first metal plate and the second metal plate, and formed of aluminum powder. The gadolinium oxide particles are dispersed in the base material.

  According to the aspect of the present invention, since the gadolinium oxide particles are dispersed in the base material of the aluminum powder, an aluminum composite material having a neutron absorption performance and good workability is provided. Moreover, since the 1st metal plate and 2nd metal plate which pinch | interpose a base material are provided, the aluminum composite material which has the intensity | strength expected is provided.

  As an aspect of the present invention, the base material may contain the gadolinium oxide particles in an amount of 6% by mass to 30% by mass. Thereby, an aluminum composite material having neutron absorption performance and good workability is provided.

  As one aspect of the present invention, the base material contains the gadolinium oxide particles in an amount of 6% by mass to 30% by mass, an elongation rate of 8% or more, and a radius of curvature that does not cause a crack when subjected to a 90-degree bending test. When R and the thickness are Da, the formability represented by the minimum value of the ratio R / Da may be 2.3 or more and 6.0 or less. Thereby, an aluminum composite material having neutron absorption performance and good workability is provided.

  As one embodiment of the present invention, boron carbide particles may be further dispersed in the base material. Thereby, an aluminum composite material having a good balance in characteristics such as neutron absorption performance, workability, and manufacturing cost is provided.

  As one aspect of the present invention, boron carbide particles are further dispersed in the base material, the gadolinium oxide particles are contained in the base material in an amount of 2% by mass to 10% by mass, and the boron carbide particles are 10% by mass or more. You may contain 20 mass% or less. Thereby, an aluminum composite material having neutron absorption performance and good workability is provided.

  As one embodiment of the present invention, boron carbide particles are further dispersed in the base material, the gadolinium oxide particles are contained in the base material in an amount of 2% by mass to 20% by mass, and the boron carbide particles are 10% by mass or more. It may be contained in an amount of 20% by mass or less, and the elongation may be 2% or more. Thereby, an aluminum composite material having neutron absorption performance and good workability is provided.

  As one aspect of the present invention, boron carbide particles are further dispersed in the base material, the gadolinium oxide particles are contained in the base material in an amount of 2% by mass to 10% by mass, and the boron carbide particles are 10% by mass or more. It is contained by 20% by mass or less, the elongation is 6% or more, and when the radius of curvature is R and the thickness is Da, when the 90-degree bending test is performed, the minimum value of the ratio R / Da is expressed. The moldability may be 4.5 or more and 7.5 or less. Thereby, an aluminum composite material having neutron absorption performance and good workability is provided.

  As one aspect of the present invention, at least one of the first metal plate and the second metal plate may be made of aluminum or stainless steel. Thereby, the aluminum composite material which has corrosion resistance and has the expected strength is provided.

  The method for producing an aluminum composite material according to an aspect of the present invention includes a step of mixing aluminum powder and gadolinium oxide particles, a step of filling a case with the mixed material generated by the mixing, and forming a rolled body, A step of heating the rolled body, and a step of rolling the heated rolled body to produce an aluminum composite.

  According to the aspect of the present invention, after mixing aluminum powder and gadolinium oxide particles to produce a mixed material, the mixed material is filled in a case and rolled, so that the gadolinium oxide particles are uniformly dispersed in the aluminum powder. Aluminum composites can be manufactured. Thereby, an aluminum composite material having neutron absorption performance and good workability can be manufactured.

  As one aspect of the present invention, the mixing may be performed so that the gadolinium oxide particles are contained in the mixed material in an amount of 6% by mass to 30% by mass. Thereby, an aluminum composite material having neutron absorption performance and good workability can be manufactured.

  As one aspect of the present invention, the mixing step may further include mixing boron carbide particles. Thereby, an aluminum composite material having a good balance in characteristics such as neutron absorption performance, workability, and manufacturing cost can be manufactured.

  As one aspect of the present invention, the mixing step further includes mixing boron carbide particles, the gadolinium oxide particles are contained in the mixed material in an amount of 2% by mass to 20% by mass, and the boron carbide particles The said mixing may be performed so that it may contain 10 mass% or more and 20 mass% or less. Thereby, an aluminum composite material having neutron absorption performance and good workability can be manufactured.

  As one aspect of the present invention, the case includes a first case and a second case, and the step of forming the body to be rolled includes filling the mixed material in a recess of the first case, and the mixing Covering the opening of the recess filled with the material with the second case. Thereby, a mixed material can be smoothly filled in a case.

  One aspect of the present invention may include tapping the first case in the filling of the mixed material into the first case. Thereby, the filling density of the mixed material in the first case can be increased.

  As an aspect of the present invention, the first case is arranged such that the upper surface of the mixed material filled in the concave portion of the first case and the upper surface of the first case around the concave portion are arranged in the same plane. May be filled with the above-mentioned mixed material. Thereby, after filling a 1st case with a mixed material, a 1st case and a 2nd case can be joined smoothly.

  According to the aspect of the present invention, an aluminum composite material having neutron absorption performance and good workability can be provided.

FIG. 1 is a cross-sectional view showing an example of an aluminum composite material according to the present embodiment. FIG. 2 is a flowchart showing an example of a method for producing an aluminum composite material according to the present embodiment. FIG. 3 is a perspective view showing an example of a case used in the method for producing an aluminum composite material according to the present embodiment. FIG. 4 is a diagram illustrating an example of a case and a reinforcing material used in the method for producing an aluminum composite material according to the present embodiment. FIG. 5 is a cross-sectional view showing an example of a member to be rolled. FIG. 6 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and shows an example in which the first case is prepared. FIG. 7 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and shows a state in which the first case and the extension sleeve are overlapped. FIG. 8 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and shows a state in which the mixed material is put into the space formed by the first case and the extension sleeve. It is. FIG. 9 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and the tapping is performed by introducing the mixed material into the space formed by the first case and the extension sleeve. FIG. FIG. 10 is a view for explaining an example of the manufacturing method of the aluminum composite material according to this embodiment, and shows a state in which the extension sleeve is removed from the first case. FIG. 11 is a diagram for explaining an example of the method for manufacturing the aluminum composite material according to the present embodiment, and shows a state in which at least a part of the mixed material of the first case has been recovered. FIG. 12 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and shows a state in which the opening of the first case is covered with the second case. FIG. 13 is a view for explaining an example of the manufacturing method of the aluminum composite material according to the present embodiment, and is a view showing a state in which the material to be rolled is formed by filling the case with the mixed material. . FIG. 14 is a photograph showing an example of the base material according to the example. FIG. 15 is a photograph showing an example of a base material according to the example. FIG. 16 is a photograph showing an example of a base material according to the example. FIG. 17 is a photograph showing an example of a base material according to the example. FIG. 18 is a photograph showing an example of a base material according to the example. FIG. 19 is a photograph showing an example of a base material according to the example. FIG. 20 is a photograph showing an example of a base material according to the example. FIG. 21 is a photograph showing an example of a base material according to the example. FIG. 22 is a photograph showing an example of a base material according to the example. FIG. 23 is a photograph showing an example of a base material according to a comparative example.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings, but the present invention is not limited thereto. The components of the embodiments described below can be combined as appropriate. Some components may not be used. In addition, constituent elements in the embodiments described below include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range.

[Structure of aluminum composite]
FIG. 1 is a cross-sectional view schematically showing an example of the aluminum composite material 100 according to the present embodiment. In the present embodiment, aluminum is a concept including one or both of pure aluminum and an aluminum alloy.

  In FIG. 1, an aluminum composite material 100 includes a metal plate 1, a metal plate 2, and a base material 3 disposed between the metal plate 1 and the metal plate 2. One surface of the base material 3 and the metal plate 1 are in contact with each other, and the other surface of the base material 3 facing the opposite direction of the one surface is in contact with the metal plate 2. The base material 3 is sandwiched between the metal plate 1 and the metal plate 2. The base material 3 may be referred to as the core material 3, and the metal plate 1 and the metal plate 2 may be referred to as the skin material 1 and the skin material 2, respectively.

The base material 3 is made of aluminum powder, and particles having neutron absorption performance are dispersed in the base material 3. The neutron absorption performance includes a function of inhibiting neutron transmission. In the present embodiment, gadolinium oxide particles are dispersed in the base material 3. Gadolinium oxide (Gd ₂ O ₃ ) is a material having neutron absorption performance. In this embodiment, the base material 3 may contain 6% by mass or more and 30% by mass or less of gadolinium oxide particles. The base material 3 may be produced from aluminum powder and gadolinium oxide particles. When the base material 3 is produced | generated from aluminum powder and a gadolinium oxide particle, the base material 3 may be produced | generated from 6 mass% or more and 30 mass% or less gadolinium oxide particle, and the remainder aluminum powder.

Further, boron carbide particles may be dispersed in the base material 3. Boron carbide (B ₄ C) is a material having neutron absorption performance. In the present embodiment, the base material 3 may contain 2% by mass or more and 20% by mass or less of gadolinium oxide particles, and may contain 10% by mass or more and 20% by mass or less of boron carbide particles. The base material 3 may contain 2% by mass or more and 10% by mass or less of gadolinium oxide particles, and may contain 10% by mass or more and 20% by mass or less of boron carbide particles. Base material 3 may be generated from aluminum powder, gadolinium oxide particles, and boron carbide particles. When the base material 3 is produced from aluminum powder, gadolinium oxide particles and boron carbide particles, the base material 3 is composed of 2% by mass to 10% by mass of gadolinium oxide particles and 10% by mass to 20% by mass of carbonization. It may be produced from boron particles and the remaining aluminum powder.

  In the following description, one or both of gadolinium oxide particles and boron carbide particles having neutron absorption performance are appropriately referred to as neutron absorption particles.

  The metal plate 1 and the metal plate 2 are each made of aluminum. Both the metal plate 1 and the metal plate 2 may be made of stainless steel, or one of the metal plate 1 and the metal plate 2 may be made of aluminum and the other may be made of stainless steel.

  The thickness Da of the aluminum composite material 100 is a total value of the thickness D1 of the metal plate 1, the thickness D2 of the metal plate 2, and the thickness D3 of the base material 3. In the present embodiment, the total value (D1 + D2) of the thickness D1 of the metal plate 1 and the thickness D2 of the metal plate D2 is set to 15% or more and 25% or less of the thickness Da of the aluminum composite material 100.

[Description of raw materials]
(Aluminum powder)
The aluminum powder of the base material 3 will be described. The aluminum powder that forms the base material 3 may be formed of, for example, an aluminum alloy defined by A1100 according to JIS standards (AA1100 according to AA standards). In the present embodiment, the aluminum powder has a total of 0.95% by weight or less of silicon (Si) and iron (Fe), 0.05% to 0.20% by weight of copper (Cu), and manganese (Mn). It is formed from a material having a composition of 0.05% by mass or less, zinc (Zn) of 0.10% by mass or less, and the remainder being aluminum and inevitable impurities.

  The composition of the aluminum powder is not limited to the above composition. For example, the aluminum powder is pure aluminum (JIS1050, JIS1070, etc.), Al—Cu alloy (JIS2017, etc.), Al—Mg—Si alloy (JIS6061, etc.), Al—Zn—Mg alloy (JIS7075, etc.), and You may form from the at least 1 alloy of an Al-Mn type alloy.

  The composition of the aluminum powder may be determined in consideration of required characteristics, moldability, the amount of particles to be mixed, raw material costs, and the like. For example, when it is desired to improve the workability or heat dissipation of the aluminum composite material 100, the aluminum powder is preferably pure aluminum powder. Pure aluminum powder is more advantageous in terms of raw material costs than aluminum alloy powder. In addition, it is preferable to use a pure aluminum powder having a purity of 99.5% by mass or more.

  The upper limit value of the average particle diameter of the aluminum powder is, for example, 200 μm or less, preferably 100 μm or less, more preferably 30 μm or less. The lower limit of the average particle diameter of the aluminum powder is, for example, 0.5 μm or more, preferably 10 μm or more. The average particle size of the aluminum powder is not particularly limited as long as it can be produced. In the present embodiment, an aluminum powder having an average particle size of 0.5 μm or more and 200 μm or less, preferably 10 μm or more and 30 μm or less is used.

  The average particle diameter of the aluminum powder is 100 μm or less, and the average particle diameter of the neutron absorbing particles (one or both of gadolinium oxide particles and boron carbide particles) is 30 μm or less. The portion in which the aluminum composite material 100 is uniformly dispersed and the neutron absorbing particles are thin is reduced, and the characteristics of the aluminum composite material 100 are stabilized.

  When the difference between the average particle diameter of the aluminum powder and the average particle diameter of the neutron absorbing particles is large, there is a high possibility that the base material 3 will crack in the rolling process described later. Therefore, it is preferable that the difference between the average particle size of the aluminum powder and the average particle size of the neutron absorbing particles is small.

  Moreover, when the average particle diameter of aluminum powder is too large, possibility that it will become difficult for aluminum powder and a neutron absorption particle to be mixed uniformly becomes high. On the other hand, when the average particle diameter of the aluminum powder is too small, aggregation tends to occur between the aluminum powders, and there is a high possibility that it is difficult to uniformly mix the aluminum powder and the neutron absorbing particles. By setting the average particle size of the aluminum powder within the above range, excellent workability, formability, and mechanical properties can be obtained.

  The average particle diameter of the aluminum powder is a value determined by a laser diffraction particle size distribution measurement method. For example, the average particle diameter of the aluminum powder may be measured by “Microtrack” manufactured by Nikkiso Co., Ltd. The average particle diameter is a volume-based median diameter. The shape of the aluminum powder is not particularly limited. The shape of the aluminum powder may be any shape such as a teardrop shape, a true spherical shape, a spheroid shape, a flake shape, and an indefinite shape. In addition, the average particle diameter of the gadolinium oxide particle | grains mentioned later, the average particle diameter of a boron carbide particle, and the average particle diameter of another particle | grain can be measured with the same method.

  The aluminum powder can be manufactured according to a known metal powder manufacturing method. The manufacturing method of aluminum powder is not limited. Examples of the method for producing the aluminum powder include an atomizing method, a melt spinning method, a rotating disk method, a rotating electrode method, and other rapid solidification methods. From the viewpoint of industrial production, the atomizing method is preferable, and the gas atomizing method is more preferable.

  In the atomization method, it is preferable to atomize the molten metal usually by heating it to 700 ° C. or more and 1200 ° C. or less. By setting to this temperature range, more effective atomization can be performed. The atomizing medium / atmosphere during atomization may be air, nitrogen, argon, helium, carbon dioxide, water, or a mixture thereof, but the atomizing medium is air, nitrogen gas or argon gas from an economic viewpoint. Is preferred.

(Gadolinium oxide particles)
Next, the gadolinium oxide particles dispersed in the base material 3 will be described. Gadolinium oxide (Gd ₂ O ₃ ) has neutron absorption performance, and the gadolinium oxide particles are dispersed in the base material 3 so that the aluminum composite material 100 functions as a neutron absorber.

  The gadolinium oxide particles are preferably contained in the aluminum powder in an amount of 6.0% by mass or more and 30.0% by mass or less. When the amount is less than 6% by mass, there is a high possibility that the base material 3 cannot have sufficient neutron absorption performance. On the other hand, when it is more than 30% by mass, there is a high possibility that the molded body becomes brittle and easily breaks. In addition, the bondability between the aluminum powder and the gadolinium oxide particles is also deteriorated, voids are easily formed, the desired functions cannot be obtained, and the strength and thermal conductivity are likely to be lowered. Further, the machinability of the aluminum composite material 100 is likely to deteriorate.

  The average particle diameter of the gadolinium oxide particles is arbitrary, and the difference between the average particle diameter of the aluminum powder and the average particle diameter of the gadolinium oxide particles is appropriately selected according to the required specifications. In this embodiment, the average particle diameter of the gadolinium oxide particles is 1 μm or more and 30 μm or less. When the average particle diameter of the gadolinium oxide particles is larger than 30 μm, there is a high possibility that problems such as the wear of the cutting tool immediately occur during cutting. On the other hand, when the average particle diameter of the gadolinium oxide particles is smaller than 1 μm, aggregation is likely to occur between the fine gadolinium particles, which may make it difficult to uniformly mix the aluminum powder and the gadolinium oxide particles. Becomes higher.

  The average particle diameter of the gadolinium oxide particles is a value determined by a laser diffraction particle size distribution measurement method. The shape of the gadolinium oxide particles is not limited, and may be any of, for example, a teardrop shape, a true spherical shape, a spheroid shape, a flake shape, and an indefinite shape.

(Boron carbide particles)
Next, the boron carbide particles will be described. In the present embodiment, not only gadolinium oxide particles but also boron carbide particles may be dispersed in the base material 3 formed of aluminum powder. Boron carbide (B ₄ C) has neutron absorption performance, and the aluminum composite material 100 functions as a neutron absorber by dispersing gadolinium oxide particles and boron carbide particles in the base material 3.

  When the gadolinium oxide particles are contained in the aluminum powder in an amount of 2 to 20% by mass, the boron carbide particles are preferably contained in an amount of 10 to 20% by mass. When the amount of boron carbide particles is less than 10% by mass, it is highly likely that the base material 3 cannot have sufficient neutron absorption performance. On the other hand, when the amount of boron carbide particles is more than 20% by mass, there is a high possibility that the molded body becomes brittle and easily breaks. In addition, when boron carbide particles are contained in the aluminum powder in an amount of 10% by mass or more and 20% by mass or less, the gadolinium oxide particles may be contained in an amount of 2% by mass or more and 10% by mass or less.

  The average particle diameter of the boron carbide particles is arbitrary, and the difference between the average particle diameter of the aluminum powder and the average particle diameter of the boron carbide particles is appropriately selected according to the required specifications. In this embodiment, the average particle diameter of the boron carbide particles is 1 μm or more and 30 μm or less. When the average particle diameter of the boron carbide particles is larger than 30 μm, there is a high possibility that problems such as the wear of the cutting tool immediately occur during cutting. On the other hand, when the average particle diameter of the boron carbide particles is smaller than 1 μm, the fine boron carbide particles are likely to aggregate with each other, so that it is difficult to uniformly mix the aluminum powder and the boron carbide particles.

  The average particle size of the boron carbide particles is a value determined by a laser diffraction particle size distribution measurement method. The powder shape of the boron carbide particles is not limited, and may be any of, for example, a teardrop shape, a true spherical shape, a spheroid shape, a flake shape, and an indefinite shape.

Note that the base material 3 may or may not contain boron carbide particles. Further, the base material 3 may contain other particles in addition to the gadolinium oxide particles. Ceramic particles may be contained as particles contained in the base material 3. Examples of the ceramic contained in the base material 3 include Al ₂ O ₃ , SiC, BN, aluminum nitride, and silicon nitride in addition to B ₄ C. These ceramics are used in powder form, and these can be used alone or as a mixture, and are selected depending on the use of the composite material.

Since boron (B) has neutron absorption performance, when boron-based ceramic particles are used, the aluminum composite material 100 can be used as a neutron absorber. In that case, examples of the boron-based ceramic include TiB ₂ , B ₂ O ₃ , FeB, and FeB ₂ in addition to the above-described B ₄ C. These boron-based ceramics are used in the form of powder, and these can be used alone or as a mixture. In particular, it is preferable to use boron carbide B ₄ C containing a large amount of ¹⁰ B, which is an isotope of B that absorbs neutrons well. The average particle diameter of these ceramic particles is arbitrary, but is preferably 1 μm or more and 30 μm or less, and more preferably 5 μm or more and 20 μm or less.

  If it is desired to further impart neutron absorption performance to the base material 3, in other words, if it is desired to keep neutron permeability low, at least one having neutron absorption performance such as hafnium (Hf), samarium (Sm), gadolinium (Gd), etc. Seed elements may be added to the aluminum powder. When high temperature strength is required, titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), magnesium (Mg), iron (Fe), copper (Cu), nickel (Ni ), Molybdenum (Mo), niobium (Nb), zirconium (Zr), strontium (Sr) and the like may be added to the aluminum powder. When room temperature strength is required, at least one of silicon (Si), iron (Fe), copper (Cu), magnesium (Mg), zinc (Zn) and the like may be added to the aluminum powder.

[Production method]
Next, an example of a method for manufacturing the aluminum composite material 100 according to the present embodiment will be described. In the following description, an example in which the base material 3 is generated from aluminum powder and gadolinium oxide particles will be described.

  As shown in the flowchart of FIG. 2, the manufacturing method of the aluminum composite material 100 according to the present embodiment includes a mixing step (step S1) in which aluminum powder and gadolinium oxide particles are mixed to generate a mixed material M, and a mixing step. A case preparing step (step S2) for preparing the case 10 for filling the mixed material M generated by the above, a reinforcing material preparing step (step S3) for preparing the reinforcing member 16 for reinforcing the case 10, and mixing. The filling step (step S4) for filling the case 10 with the mixed material M generated in the process to form the rolled body 18, the preheating step (step S5) for heating the rolled body 18, and the heated rolled roll A rolling step (step S6) in which the body 18 is rolled to produce the aluminum composite material 100.

(Step S1: mixing process)
Aluminum powder and gadolinium oxide particles are prepared and mixed uniformly. The aluminum powder may be one kind or a mixture of plural kinds. In the mixing step, mixing is performed so that the admixture M of aluminum powder and gadolinium oxide particles contains 6% by mass to 30% by mass of gadolinium oxide particles. The mixing method of the aluminum powder and the gadolinium oxide particles may be a known method. For example, various mixers such as a V blender and a cross rotary mixer, a vibration mill, a planetary mill, etc. may be used for mixing for a predetermined time. In this embodiment, the mixing time is 10 minutes or longer and 10 hours or shorter, preferably 3 hours or longer and 6 hours or shorter. Further, the mixing may be either dry or wet. In addition, an abrasive medium such as alumina or a SUS ball may be appropriately added for the purpose of crushing during mixing.

  In the mixing step, the mixed material M produced by mixing the aluminum powder and the gadolinium oxide particles is sent to the next step as it is.

(Step S2: Case preparation process)
In the case preparation process, a hollow flat metal case 10 filled with the mixed material M generated in the above-described mixing process is prepared. FIG. 3 is an exploded perspective view showing an example of the case 10. FIG. 4 is a diagram illustrating an example of the structure of the case 10. FIG. 5 is a cross-sectional view showing an example of the rolled body 18 including the case 10 and the mixed material M filled in the case 10.

  Case 10 is preferably made of aluminum or stainless steel. For example, in the case of the case 10 made of aluminum, pure aluminum (JIS 1050, JIS 1070, etc.) is preferably used. In addition, as a material for forming the case 10, an Al—Cu alloy (JIS2017 etc.), an Al—Mg alloy (JIS5052 etc.), an Al—Mg—Si alloy (JIS6061 etc.), an Al—Zn—Mg alloy ( Various types of alloy materials such as JIS7075) and Al-Mn alloys can also be used.

  The composition of aluminum to be selected may be determined in consideration of required characteristics and cost. For example, when it is desired to improve workability or heat dissipation, the case 10 is preferably formed of pure aluminum. Pure aluminum is advantageous in terms of raw material costs compared to the case of an aluminum alloy. Further, when it is desired to further increase the strength and workability of the case 10, the case 10 is preferably formed of an Al—Mg alloy (JIS 5052 or the like). Furthermore, when it is desired to improve the neutron absorption performance, at least one element having neutron absorption performance such as Hf, Sm, Gd may be added to the case 10 in an amount of 1 to 50 mass%.

  In the present embodiment, the case 10 includes a lower case (first case) 12 and an upper case (second case) 14, and the lower case 12 and the upper case 14 are prepared in the case preparation step. Each of the lower case 12 and the upper case 14 is formed of the same material, and is made of aluminum in the present embodiment. As shown in FIGS. 3, 4, and 5, the lower case 12 includes a side plate 12A, a side plate 12B facing the side plate 12A, a front plate 12C, a rear plate 12D facing the front plate 12C, and a bottom plate 12E. And have. The upper case 14 includes a side plate 14A, a side plate 14B facing the side plate 14A, a front plate 14C, a rear plate 14D facing the front plate 14C, and an upper plate 14E.

  The lower case 12 is formed in a bottomed rectangular parallelepiped shape whose upper surface is open, and has a recess 12H filled with the mixed material M. The upper case 14 is formed in a substantially rectangular parallelepiped shape, and functions as a closing member that closes the upper surface of the opened lower case 12. The upper case 14 has a size slightly larger than the lower case 12 and is fitted so as to cover the outer periphery of the lower case 12 from above the lower case 12. The upper case 14 is disposed so as to cover the opening 12K at the upper end of the recess 12H filled with the mixed material M.

(Step S3: Stiffener preparation process)
A reinforcing material (reinforcing frame) 16 for reinforcing the outer periphery of the case 10 is prepared. The reinforcing material 16 is disposed to reinforce the outer peripheral surface of the case 10 in the rolling process. When the case 10 is rolled, the case 10 has a longitudinal direction of the case 10 (in the case where the planar shape of the case 10 is a square, any central axis) along the rolling direction, and the extending surface thereof is in the horizontal direction. It is arranged along.

  The side plate 14A and the side plate 14B of the upper case 14 are arranged along the rolling direction, and the front plate 14C and the rear plate 14D are arranged along a direction orthogonal to the rolling direction. The reinforcing member 16 includes a first reinforcing member 16A connected to the side plate 14A, a second reinforcing member 16B connected to the side plate 14B, a third reinforcing member 16C connected to the front plate 14C, and a rear plate. And a fourth reinforcing member 16D connected to 14D.

  The first reinforcing member 16A is attached to the side plate 14A, and the second reinforcing member 16B is attached to the side plate 14B. The first reinforcing member 16A has both ends of the first reinforcing member 16A extending forward and backward from the side plate 14A in the rolling direction, and the second reinforcing member 16B has both ends of the second reinforcing member 16B in the rolling direction. Extends beyond the side plate 14B.

  The third reinforcing member 16C is attached to the front plate 14C, and the fourth reinforcing member 16D is attached to the rear plate 14D. The third reinforcing member 16C has the same length as the front plate 14C in the direction orthogonal to the rolling direction, and the fourth reinforcing member 16D is the same as the rear plate 14D in the direction orthogonal to the rolling direction. Has a length.

(Step S4: filling step)
Next, the mixed material M generated in the above-described mixing step is filled in the concave portion 12H of the lower case 12. The filling step includes an operation of uniformly feeding the mixed material M. In the filling operation (uniform charging operation) of the mixed material M to the lower case 12, the lower case 12 is tapped. Tapping includes a process of hitting the lower case 12. The tapping may be performed in parallel with at least a part of the uniform charging operation, or may be performed after the uniform charging operation. By tapping, the filling density of the mixed material M in the lower case 12 can be increased. Tapping is performed so that the theoretical filling rate of the mixed material M is in the range of 35% to 65%.

  6 to 13 are diagrams illustrating an example of a filling process for forming the rolled body 18. As shown in FIG. 6, the lower case 12 is arranged at a predetermined filling position so that the opening 12K of the recess 12H faces upward. Next, as shown in FIG. 7, the extension sleeve 20 is disposed on the lower case 12 so that the extension sleeve 20 and the lower case 12 overlap each other. In a state where the extension sleeve 20 and the lower case 12 are overlapped, the extension sleeve 20 includes a sleeve body 20A having a lower surface that can be in close contact with the upper surface 12J of the lower case 12 around the recess 12H, and an outer side from the lower surface of the sleeve body 20A. And a skirt portion 20B fitted to the lower case 12 from the outside in a state where the lower surface of the sleeve body 20A and the upper surface 12J of the lower case 12 are in contact with each other.

  In this way, with the extension sleeve 20 overlaid on the lower case 12, as shown in FIG. 8, the mixed material M is introduced into the space formed by the lower case 12 and the extension sleeve 20.

  In the present embodiment, the lower case 12 and the extension sleeve 20 are tapped in a state where the mixed material M is put into a space formed by the lower case 12 and the extension sleeve 20. That is, one or both of the lower case 12 and the extension sleeve 20 are hit. As a result, as shown in FIG. 9, the filling density of the mixed material M is increased in the space formed by the lower case 12 and the extension sleeve 20, and the upper surface of the mixed material M is lowered.

  Then, when a predetermined tapping time has elapsed and the filling density of the mixed material M reaches a required filling density, the tapping is stopped, and the extension sleeve 20 is lifted upward and removed from the lower case 12. As a result, as shown in FIG. 10, the mixed material M is disposed in the recess 12 </ b> H of the lower case 12, and a part of the mixed material M present in the extension sleeve 20 protrudes above the lower case 12. Placed in.

  Thereafter, the scraper 22 moves along the upper surface 12J of the lower case 12, so that a part of the mixed material M protruding above the lower case 12 is frayed, and as shown in FIG. The material M is collected in the collection box 24. Note that the mixed material M collected in the collection box 24 is returned to the blender described above, stirred again, and reused.

  By partially scraping the mixed material M, the concave portion 12H of the lower case 12 is fully filled with the mixed material M having a high packing density. In the present embodiment, the upper surface of the mixed material M filled in the recess 12H of the lower case 12 and the upper surface 12J of the lower case 12 around the recess 12H are arranged in the same plane (being flush with each other).

  Thereafter, as shown in FIG. 12, the upper case 14 and the lower case 12 are fitted, and the opening 12 </ b> K of the recess 12 </ b> H filled with the mixed material M is covered with the upper case 14. In a state where the opening 12K of the lower case 12 is closed, as shown in FIG. 13, the rolled body 18 in which the mixed material M is fully filled is formed inside the case 10.

  Here, the state of the to-be-rolled body 18 shown in FIG. 13 is extremely “a material” (meaning a material to be rolled in the rolling process described later) for producing the aluminum composite material 100 according to the present embodiment. Has an important meaning. Although details will be described later, in the three-layer clad structure obtained by rolling the rolled body 18, the bottom plate 12E of the lower case 12 defines the lowermost layer (skin layer), and the mixed material M is the intermediate layer (core layer). ) And the upper plate 14E of the upper case 14 defines the uppermost layer (skin layer).

  In order for this three-layer clad structure to exhibit sufficient mechanical properties, adjacent layers need to be in close contact with each other. In the present embodiment, the lower surface of the mixed material M and the upper surface of the bottom plate 12E of the lower case 12 are in close contact with each other, and the upper surface of the mixed material M and the lower surface of the upper plate 14E of the upper case 14 are spread over the entire surface. It is in close contact. In this embodiment, it rolls in the state which adjacent layers closely_contact | adhered, and in the three-layer clad structure after rolling, these layers are joined firmly. Therefore, the mechanical strength of the aluminum composite material 100 having a three-layer clad structure is sufficiently secured.

  Next, the work of reinforcing the object to be rolled 18 with the reinforcing material 16 is performed. As shown in FIG. 5, the reinforcing work includes surrounding the outer periphery of the rolled body 18 excluding the upper and lower surfaces in the rolling posture with the reinforcing material 16.

  That is, the first reinforcing member 16A is temporarily fixed to the side plate 14A of the upper case 14, and the second reinforcing member 16B is temporarily fixed to the side plate 14B of the upper case 14. With respect to the rolling direction, both ends of the first reinforcing member 16A extend from the side plate 14A, and temporarily fixed so that both ends of the second reinforcing member 16B extend from the side plate 14B. Next, the third reinforcing member 16C is temporarily fixed to the front plate 14C of the upper case 14, and the fourth reinforcing member 16D is temporarily fixed to the rear plate 14D of the upper case 14. One end of the third reinforcing member 16C abuts on the end of the first reinforcing member 16A in the direction orthogonal to the rolling direction, and the other end of the third reinforcing member 16C contacts the end of the second reinforcing member 16B. Temporarily fastened to touch. One end of the fourth reinforcing member 16D is in contact with the end of the first reinforcing member 16A in the direction orthogonal to the rolling direction, and the other end of the fourth reinforcing member 16D is in contact with the end of the second reinforcing member 16B. Temporarily fastened to touch.

  Thus, in a state where the reinforcing material 16 is temporarily fixed to the rolled body 18, the rolled body 18 is placed in a vacuum furnace, depressurized at a predetermined degree of vacuum, and degassed.

  After the degassing operation is finished, the temporarily fixed reinforcing material 16 is fixed to the rolled body 18 by MIG welding. MIG welding is performed by welding the upper edge of the reinforcing material 16 and the upper edge of the upper case 14 over the entire circumference, and welding the lower edge of the reinforcing material 16 and the lower edge of the upper case 14 over the entire circumference. carry out. Here, the lower edge of the upper case 14 and the lower edge of the lower case 12 are closely adjacent to each other. As a result, when the lower edge of the reinforcing member 16 and the lower edge of the upper case 14 are welded, the lower edge of the lower case 12 is also welded together. As a result, the case 10 is hermetically sealed as a whole. It will be.

  Here, since the case 10 is hermetically sealed, when air is present (residual) in the rolled body 18, this may remain as a defect. For this reason, in order to prevent air from escaping from the inside of the body to be rolled 18 and not remaining in the rolling process, air vent holes (not shown) are formed in the four corners of the upper surface of the upper case 14 or welding is performed. A gap may be formed in the case partially. The formation of the holes and gaps can also be expected to remove the gas that has entered the rolled material 18 during welding.

(Step S5: Preheating process)
The rolled body 18 reinforced with the reinforcing material 16 is preheated (heated) before being rolled. Preheating is carried out in a heating furnace by leaving it in an air atmosphere in the range of 300 ° C. to 600 ° C. for 2 hours or longer. In this embodiment, preheating is performed at 500 ° C. for 2 hours or more. Here, the preheating atmosphere is not limited to being performed in the air. It is preferable to carry out in an inert gas such as argon. More preferably, it is performed in a vacuum atmosphere of 5 Pa or less. In the preheating step, the rolling target 18 is heated so that the powder state of the mixed material M is maintained.

(Step S6: Rolling process)
In the rolling process, a plastic processing called rolling is performed on the body to be rolled 18. First, a situation in which the rolling body 18 has a specific effect in the present embodiment will be described.

  That is, in the to-be-rolled body 18 rolled in the rolling process, the mixed material M to be rolled remains as a powder and is not solidified at all. That is, as before, before being subjected to the rolling process, it is preformed for the purpose of maintaining the shape, and more specifically, it is preliminarily pressed into the desired shape by pressing or conducting current and pressure sintering. It is something that is not considered to be molded. In the to-be-rolled body 18 in the present embodiment, although the filling rate is increased by the above-described tapping, the state as a powder is maintained rather than a solidified one.

  Further, when being used in the rolling process, the upper and lower sides of the mixed material M as powder are sandwiched between aluminum cases 10 (lower case 12 and upper case 14). Specifically, the upper surface of the mixed material M is covered entirely and tightly by the upper plate 14E of the upper case 14, and the lower surface of the mixed material M is covered by the bottom plate 12E of the lower case 12. It is completely and closely covered. Thus, this to-be-rolled body 18 is a plate-like clad material as a three-layer clad structure in which the mixed material M is filled in the case 10 and sealed, and the mixed material M is sandwiched between the upper and lower aluminum plates. "Material" is specified.

  The pre-rolled material 18 is rolled and formed into a target shape. When producing a plate-like clad material, it is also possible to obtain a clad plate material having a predetermined clad rate with an Al plate material or an Al container only by cold rolling. One processing may be performed by hot plastic processing, or a plurality of processing may be combined. Further, cold plastic working may be performed after hot plastic working. In the case of performing cold plastic working, if annealing is performed at 300 ° C. to 600 ° C. (preferably 400 ° C. to 500 ° C.) before the processing, the processing becomes easy.

  Since the to-be-rolled body 18 is clad with the aluminum plate, there are no ceramic particles on its surface that become the starting point of fracture during plastic working or wear dies. Therefore, it is possible to obtain an aluminum composite material 100 having excellent rolling processability and excellent strength and surface properties. Moreover, since the surface of the obtained hot plastic working material is clad with a metal and the adhesion between the surface metal and the inner mixed material M is good, the aluminum composite material 100 whose surface is not clad with the metal material, Excellent corrosion resistance, impact resistance and thermal conductivity.

  In another preferred embodiment, it is also effective to cover the surface of the object to be rolled 18 with a metal protective plate, for example, a thin plate made of SUS or Cu before rolling. As a result, it is possible to prevent cracks and cracks in the front-rear direction that may occur during plastic processing.

  More specifically, in the rolling step, hot rolling is performed by repeatedly performing 10 to 14 passes in a range of a rolling reduction of 10% to 70%. The rolling temperature in this hot rolling is set to 500 ° C.

  In addition, you may finish to desired final thickness by this hot rolling. Moreover, you may perform warm rolling in the range of 200 to 300 degreeC after this hot rolling. Furthermore, after this warm rolling, the second warm rolling may be performed at a temperature of 200 ° C. or lower.

  And after a rolling process is complete | finished, the heat processing process of the predetermined time in the range of 300 to 600 degreeC, ie, an annealing process, is implemented. After this annealing process, a cooling process is performed, a correction process for correcting to a desired flatness is performed, and both side edges, leading edge, and trailing edge are cut off to obtain a predetermined product shape (aluminum composite material). 100 plate clad material). For example, after this rolling, annealing may be performed at 450 ° C. for a predetermined time.

  In the present embodiment, the mixed material M becomes the base material 3, at least a part of the upper case 14 becomes the metal plate 1, and at least a part of the lower case 12 becomes the metal plate 2.

  In the above-described embodiment, an example in which the base material 3 is generated from aluminum powder and gadolinium oxide particles has been described. When the base material 3 is produced from aluminum powder, gadolinium oxide particles, and boron carbide particles, the aluminum powder, gadolinium particles, and boron carbide particles are mixed in the mixing step. In the mixing step, the mixture M of aluminum powder, gadolinium oxide particles, and boron carbide particles contains 2% by mass to 10% by mass of gadolinium oxide particles, and 10% by mass to 20% by mass of boron carbide particles. Mixing is performed so that it is contained below.

[Example 1]
Next, Example 1 according to the present invention will be described. As shown in Table 1, Table 2, and Table 3, samples of aluminum composite material 100 (sample 1 to sample 13) having 13 types of base materials 3 having different compositions are prepared, and the performance of each of these samples is measured. evaluated. The composition of each material can be analyzed by ICP emission spectroscopy.

Table 1 shows the composition of the base material 3 of each sample and the equivalent B ₄ C concentration of those samples. Each sample has a base material 3 having the composition shown in Table 1, and an aluminum metal plate 1 and a metal plate 2 arranged so as to sandwich the base material 3.

Sample 1 to Sample 4, Sample 6, Sample 7, and Sample 9 to Sample 11 correspond to examples according to the present invention. Samples 1 to 4 are samples in which the base material 3 is generated from aluminum powder (Al) and gadolinium oxide particles (Gd ₂ O ₃ ). Sample 6, Sample 7, Sample 9 to Sample 11 are samples in which the base material 3 is generated from aluminum powder (Al), gadolinium oxide particles (Gd ₂ O ₃ ), and boron carbide particles (B ₄ C). . Sample 5, Sample 8, Sample 12, and Sample 13 are samples according to a comparative example, and the base material 3 is a sample that does not contain gadolinium oxide particles (Gd ₂ O ₃ ).

As shown in Table 1, samples 1 to 4 are samples in which the base material 3 is generated from aluminum powder (Al) and gadolinium oxide particles (Gd ₂ O ₃ ) and does not contain boron carbide particles (B ₄ C). It is. Sample 1 contains 6% by weight of gadolinium oxide particles, Sample 2 contains 12% by weight of gadolinium oxide particles, Sample 3 contains 15% by weight of gadolinium oxide particles, and Sample 4 contains gadolinium oxide particles. Contains 30% by mass.

Samples 5 to 7 are samples in which the base material 3 contains 10% by mass of boron carbide particles (B ₄ C). Sample 5 is a sample in which base material 3 is generated from aluminum powder (Al) and boron carbide particles (B ₄ C) and does not contain gadolinium oxide particles (Gd ₂ O ₃ ). Samples 6 and 7 are samples in which the base material 3 was generated from aluminum powder (Al), gadolinium oxide particles (Gd ₂ O ₃ ), and boron carbide particles (B ₄ C). Sample 6 contains 4% by mass of gadolinium oxide particles, and sample 7 contains 10% by mass of gadolinium oxide particles.

Samples 8 to 11 are samples in which the base material 3 contains 20% by mass of boron carbide particles (B ₄ C). Sample 8 is a sample in which base material 3 is generated from aluminum powder (Al) and boron carbide particles (B ₄ C) and does not contain gadolinium oxide particles (Gd ₂ O ₃ ). Samples 9 to 11 are samples in which the base material 3 is generated from aluminum powder (Al), gadolinium oxide particles (Gd ₂ O ₃ ), and boron carbide particles (B ₄ C). Sample 9 contains 2% by mass of gadolinium oxide particles, sample 10 contains 8% by mass of gadolinium oxide particles, and sample 11 contains 20% by mass of gadolinium oxide particles.

Samples 12 and 13 are samples in which the base material 3 is generated from aluminum powder (Al) and boron carbide particles (B ₄ C) and does not contain gadolinium oxide particles (Gd ₂ O ₃ ). Sample 12 and Sample 13 contain a large amount of boron carbide particles (B ₄ C), Sample 12 contains 30% by mass of boron carbide particles, and Sample 13 contains 60% by mass of boron carbide particles.

In Table 1, the equivalent B ₄ C concentration indicates the thermal neutron absorption performance of each sample when the entire base material 3 is formed of boron carbide particles and the thermal neutron absorption performance of the base material 3 is 100. It is a relative numerical value.

  As an evaluation test, (1) a tensile test and (2) a bending test were performed. The tensile test was based on JIS-Z2241, and the tensile strength (MPa), 0.2% yield strength (MPa), and elongation (%) were measured. The bending test is based on JIS-Z2248. Samples having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm of the aluminum composite material 100 are prepared, and curvature radii of 6 mm (R6), 9 mm (R9), and 12 mm ( A bending test of 90 degrees was performed at R12), 15 mm (R15), and 20 mm (R20).

  Table 1 shows the result (tensile property) of the tensile test of each sample. Tables 2 and 3 show the bending test results of the samples.

  In addition, Sample 1, Sample 2, Sample 3, Sample 4, Sample 6 are shown in FIGS. 14, 15, 16, 17, 18, 19, 20, 21, 22, and 23, respectively. , Sample 7, Sample 9, Sample 10, Sample 11, and Sample 12 are photomicrographs taken at a magnification of 500 times using an optical microscope. As shown in FIGS. 14 to 22, in the base material 3 according to the present invention, it can be seen that neutron absorbing particles (gadolinium oxide particles, boron carbide particles) are uniformly dispersed in the aluminum powder.

Generally, gadolinium oxide particles (Gd ₂ O ₃ ) have a neutron absorption performance (thermal neutron absorption performance) that is about five times higher than that of boron carbide particles (B ₄ C). That is, the equivalent B ₄ C concentration of Sample 4 containing no boron carbide particles and containing 30% by mass of gadolinium oxide particles is 150% by mass (expected).

Moreover, as can be seen from the elongation of the tensile properties of Sample 1 to Sample 4 in Table 1, the aluminum composite material 100 having the base material 3 containing gadolinium oxide particles (Gd ₂ O ₃ ) has sufficient elongation. I understand that. As a general required specification value of growth in the market where neutron absorbers are distributed, 0.5% or more is required. Compared with this required specification value, it can be seen that the elongation of the aluminum composite material 100 having the base material 3 containing gadolinium oxide particles (Gd ₂ O ₃ ) is a high value and has sufficient elongation. . Moreover, the elongation of the sample 4 which does not contain boron carbide particles and contains 30% by mass of gadolinium oxide particles is 8.0%, does not contain gadolinium oxide particles, and contains 30% by mass of boron carbide particles. The elongation of 12 is 3.8%, and the base material 3 containing gadolinium oxide particles (Gd ₂ O ₃ ) extends more sufficiently than the base material 3 containing boron carbide particles (B ₄ C). I understand.

As can be seen from Sample 1 to Sample 4 in Table 1, when the base material 3 is produced from aluminum powder and gadolinium oxide particles, it has sufficient neutron absorption performance (equivalent B ₄ C concentration) and is sufficient In order to realize an aluminum composite material 100 having excellent tensile properties, it has been found that the base material 3 preferably contains 6% by mass or more and 30% by mass or less of gadolinium oxide particles. It can be seen that when gadolinium oxide particles are contained within the numerical range, sufficient values can be obtained not only for the tensile properties but also for the tensile strength and 0.2% proof stress.

  The tensile strength in the market where neutron absorbers are distributed is required to be 35 MPa or more as a general required specification value. As can be seen from Table 1, it can be seen that Samples 1 to 4 have sufficient tensile strength as compared with the required specification values.

  Further, the 0.2% proof stress in the market where neutron absorbers are distributed is required to be 15 MPa or more as a general required specification value. As can be seen from Table 1, it can be seen that Samples 1 to 4 have sufficient 0.2% proof stress as compared with the required specification values.

As can be seen from Sample 6, Sample 7, Sample 9, and Sample 10, when the base material 3 is formed from aluminum powder, gadolinium oxide particles, and boron carbide particles, sufficient neutron absorption performance (equivalent B ₄ C concentration) ) And sufficient tensile properties, the base material 3 contains 2% by mass to 10% by mass of gadolinium oxide particles and 10% by mass of boron carbide particles. It has been found that the content is preferably 20% by mass or less. It can be seen that when gadolinium oxide particles are contained within the numerical range, sufficient values can be obtained not only for the tensile properties but also for the tensile strength and 0.2% proof stress.

  It can be seen that the higher the elongation is, the better the workability of the article is, so that the aluminum composite material 100 according to the present invention has good workability.

Incidentally, if a neutron absorbing performance when obtaining the (corresponding B _{4 C} concentration), gadolinium oxide particles boron carbide particles contained better if not the contained, both gadolinium oxide particles and boron carbide particles are contained In some cases, tensile properties (elongation) may be improved. For example, as can be seen from Sample 2 and Sample 7, for example, when an equivalent B ₄ C concentration of 60% by mass is to be obtained, the elongation of Sample 2 that does not contain boron carbide particles is 20.8%. However, the elongation of the sample 7 containing the boron carbide particles is 8.1%. As described above, in order to obtain sufficient elongation while maintaining the neutron absorption performance, the content of boron carbide particles should be small.

  On the other hand, considering the required workability (tensile properties), required neutron absorption performance, production cost, etc., whether it contains only gadolinium oxide particles or both gadolinium oxide particles and boron carbide particles May be determined. In the present embodiment, the base material 3 includes gadolinium oxide particles in consideration of the required tensile properties and the above-described required specification values (target tensile strength, target 0.2% yield strength, and target elongation). Is contained in an amount of 2% by mass or more and 10% by mass or less, and boron carbide particles are preferably contained in an amount of 10% by mass or more and 20% by mass or less.

  In Table 2 and Table 3, “x” indicates a case where cracking occurred in at least a part of the aluminum composite material 100 (in the case of NG) as a result of the bending test, and “◯” indicates that cracking did not occur. The case (in the case of OK) is shown. As shown in Tables 2 and 3, bendability also changes depending on whether only gadolinium oxide particles are contained or whether both gadolinium oxide particles and boron carbide particles are contained. Further, the test result also changes depending on the thickness Da of the aluminum composite material 100. The smaller the thickness Da, the lower the probability of becoming NG. Therefore, in consideration of required workability (bendability) and required neutron absorption performance, it is determined whether it contains only gadolinium oxide particles or both gadolinium oxide particles and boron carbide particles. May be.

  Thus, the aluminum composite material 100 (neutron absorber) according to the present embodiment exhibits a value considerably higher than the specification value required by the market in terms of its mechanical strength, and is sufficiently It has been found that it has a high mechanical strength and therefore has high industrial applicability.

[Example 2]
Next, a second embodiment according to the present invention will be described. Example 2 shows an example in which the evaluation test was performed with the number of samples increased from that in Example 1. As shown in Table 4, Table 5, and Table 6, samples of aluminum composite material 100 (sample 1 to sample 18) having 18 kinds of base materials 3 having different compositions are prepared, and the performance of each of these samples is measured. evaluated.

Table 4 shows the composition of the base material 3 of each sample and the equivalent B ₄ C concentration of those samples. Each sample has a base material 3 having the composition shown in Table 4, and an aluminum metal plate 1 and a metal plate 2 arranged so as to sandwich the base material 3.

  Sample 1 to Sample 13 shown in Table 4, Table 5, and Table 6 are the same as Sample 1 to Sample 13 of Example 1. In Example 2, Sample 14 to Sample 18 were newly added to perform an evaluation test.

  Sample 1 to Sample 4, Sample 14, Sample 6, Sample 7, Sample 9 to Sample 11, and Sample 15 correspond to examples according to the present invention.

Samples 1 to 4 and sample 14 are samples in which the base material 3 is generated from aluminum powder (Al) and gadolinium oxide particles (Gd ₂ O ₃ ) and does not contain boron carbide particles (B ₄ C).

  As shown in Table 4, Sample 1 contains 6% by mass of gadolinium oxide particles. Sample 2 contains 12% by mass of gadolinium oxide particles. Sample 3 contains 15% by mass of gadolinium oxide particles. Sample 4 contains 30% by mass of gadolinium oxide particles. Sample 14 contains 8% by mass of gadolinium oxide particles.

In Sample 6, Sample 7, Sample 9 to Sample 11, and Sample 15, the base material 3 is generated from aluminum powder (Al), gadolinium oxide particles (Gd ₂ O ₃ ), and boron carbide particles (B ₄ C). This is a sample.

  As shown in Table 4, Sample 6 contains 4% by mass of gadolinium oxide particles and 10% by mass of boron carbide particles. Sample 7 contains 10% by mass of gadolinium oxide particles and 10% by mass of boron carbide particles. Sample 9 contains 2% by mass of gadolinium oxide particles and 20% by mass of boron carbide particles. Sample 10 contains 8% by mass of gadolinium oxide particles and 20% by mass of boron carbide particles. Sample 11 contains 20% by mass of gadolinium oxide particles and 20% by mass of boron carbide particles. Sample 15 contains 5% by mass of gadolinium oxide particles and 20% by mass of boron carbide particles.

Sample 16, Sample 5, Sample 8, Sample 12, Sample 17, Sample 18, and Sample 13 are samples according to a comparative example, and the base material 3 is a sample that does not contain gadolinium oxide particles (Gd ₂ O ₃ ). .

As shown in Table 4, the sample 16 is a sample in which the base material 3 does not contain both gadolinium oxide particles (Gd ₂ O ₃ ) and boron carbide particles (B ₄ C).

In Sample 5, Sample 8, Sample 12, Sample 17, Sample 18, and Sample 13, the base material 3 is produced from aluminum powder (Al) and boron carbide particles (B ₄ C), and gadolinium oxide particles (Gd ₂ O). ₃ ) The sample does not contain.

  As shown in Table 4, Sample 5 contains 10% by mass of boron carbide particles. Sample 8 contains 20% by mass of boron carbide particles. Sample 12 contains 30% by mass of boron carbide particles. Sample 17 contains 40% by mass of boron carbide particles. Sample 18 contains 50% by mass of boron carbide particles. Sample 13 contains 60% by mass of boron carbide particles.

In Table 4, the equivalent B ₄ C concentration indicates the thermal neutron absorption performance of each sample when the entire base material 3 is formed of boron carbide particles and the thermal neutron absorption performance of the base material 3 is 100. It is a relative numerical value.

  As an evaluation test, (1) a tensile test and (2) a bending test were performed. Similar to Example 1, the tensile test was based on JIS-Z2241, and the tensile strength (MPa), 0.2% proof stress (MPa), and elongation (%) were measured. Similar to Example 1, the bending test is based on JIS-Z2248. Samples having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm for the aluminum composite material 100 were prepared, and the curvature radii were 6 mm (R6) and 9 mm. A bending test of 90 degrees was performed at (R9), 12 mm (R12), 15 mm (R15), and 20 mm (R20).

  Table 4 shows the results of the tensile test (tensile properties) and the results of the bending test (formability) of each sample. Tables 5 and 6 show the bending test results of each sample.

As can be seen from the elongation of the tensile properties of Sample 1 to Sample 4 and Sample 14 in Table 4, the aluminum composite material 100 having the base material 3 containing gadolinium oxide particles (Gd ₂ O ₃ ) is sufficiently stretched. It can be seen that

The elongation of the sample 14 containing 8% by mass of gadolinium oxide particles and no boron carbide particles is 17.4%. The elongation of sample 10 containing 8% by mass of gadolinium oxide particles and 20% by mass of boron carbide particles is 6.7%. In the base material 3 containing gadolinium oxide particles _(Gd 2 _{O 3),} towards the base material 3 content is small boron carbide particles _(B 4 C) is the mother content large boron carbide particles _(B 4 C) It can be seen that the material 3 has a sufficient elongation.

As can be seen from Sample 1 to Sample 4 and Sample 14 in Table 4, when the base material 3 is produced from aluminum powder and gadolinium oxide particles, it has sufficient neutron absorption performance (equivalent B ₄ C concentration). And in order to implement | achieve the aluminum composite material 100 which has sufficient tensile characteristics, it turns out that it is preferable that the base material 3 contains gadolinium oxide particles 6 mass% or more and 30 mass% or less. It can be seen that when gadolinium oxide particles are contained within the numerical range, sufficient values can be obtained not only for the tensile properties but also for the tensile strength and 0.2% proof stress.

As can be seen from Sample 6, Sample 7, Sample 9, Sample 10, Sample 11, and Sample 15 in Table 4, it is sufficient when the base material 3 is formed from aluminum powder, gadolinium oxide particles, and boron carbide particles. In order to realize an aluminum composite material 100 having excellent neutron absorption performance (equivalent B ₄ C concentration) and sufficient tensile properties, the base material 3 contains 2% by mass or more and 20% by mass or less of gadolinium oxide particles. It is understood that it is preferable that the boron carbide particles are contained in an amount of 10% by mass or more and 20% by mass or less. In this case, the elongation percentage of the aluminum composite material 100 is 2.1% of the sample 11, and the elongation percentage of the other samples (sample 6, sample 7, sample 9, sample 10, and sample 15) is 2.1% or more. In the example shown in Table 4, 11.2% of sample 6 is the maximum value. According to this example, the base material 3 contains 2% by mass or more and 20% by mass or less of gadolinium oxide particles, 10% by mass or more and 20% by mass or less of boron carbide particles, and the elongation is about 2% or more (2. It can be confirmed that the aluminum composite material 100 of 1% or more and 11.2% or less can be manufactured.

  As can be seen from Sample 6, Sample 7, Sample 9, Sample 10, Sample 15, and the like, when the base material 3 is generated from aluminum powder, gadolinium oxide particles, and boron carbide particles, the base material 3 is oxidized. Gadolinium particles are preferably contained in an amount of 2 to 10% by mass, and boron carbide particles are preferably contained in an amount of 10 to 20% by mass. It can be seen that when gadolinium oxide particles are contained within the numerical range, sufficient values can be obtained not only for the tensile properties but also for the tensile strength and 0.2% proof stress.

  In Tables 5 and 6, “×” indicates a case where at least a part of the aluminum composite material 100 is cracked (in the case of NG) as a result of the bending test, and “◯” indicates that no crack is generated. The case (in the case of OK) is shown.

  In this example, in order to evaluate the formability of the aluminum composite material 100, the radius of curvature R when a crack does not occur (in the case of OK) when the aluminum composite material 100 having a thickness of Da is subjected to a 90-degree bending test. The ratio R / Da was determined as an evaluation value. That is, the formability of the aluminum composite material 100 was expressed by the ratio R / Da, where R is the radius of curvature at which cracking does not occur when the 90-degree bending test is performed, and Da is the thickness.

  As shown in Table 5, the ratio R / Da when the aluminum composite material 100 having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm was subjected to a 90-degree bending test so that the radius of curvature R was 6 mm was respectively “ 6 ”,“ 3 ”,“ 1.5 ”,“ 0.75 ”.

  The ratios R / Da when the aluminum composite material 100 having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm was subjected to a 90-degree bending test so that the curvature radius R was 9 mm were “9” and “4.5”, respectively. ”,“ 2.25 ”,“ 1.125 ”.

  The ratio R / Da when the aluminum composite material 100 having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm is subjected to a 90-degree bending test so that the radius of curvature R is 12 mm is “12”, “6”, “3”, “1.5”.

  The ratio R / Da when the aluminum composite material 100 having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm was subjected to a 90-degree bending test so that the curvature radius R was 15 mm was “15” and “7.5, respectively. ”,“ 3.75 ”, and“ 1.875 ”.

  The ratio R / Da when the aluminum composite material 100 having a thickness Da of 1 mm, 2 mm, 4 mm, and 8 mm is subjected to a 90-degree bending test so that the curvature radius R is 20 mm is “20”, “10”, “5,“ 2.5 ”.

  For example, as shown in Table 5, in sample 1, when the radius of curvature R is 6 mm and the thickness Da is 1 mm and 2 mm, no crack occurs. The ratio R / Da when the radius of curvature R at which cracking does not occur is 6 mm and the thickness Da is 1 mm is “6”. The ratio R / Da when the radius of curvature R at which cracking does not occur is 6 mm and the thickness Da is 2 mm is “3”.

  Further, as shown in Table 5, in sample 1, when the radius of curvature R is 9 mm and the thickness Da is 1 mm and 2 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracks do not occur is 9 mm is “9”. The ratio R / Da when the thickness Da is 2 mm and the radius of curvature R at which the crack does not occur is 9 mm is “4.5”.

  Further, as shown in Table 5, in Sample 1, when the radius of curvature R is 12 mm and the thickness Da is 1 mm, 2 mm, and 4 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the radius of curvature R at which the crack does not occur is 12 mm is “12”. The ratio R / Da when the thickness Da is 2 mm and the radius of curvature R at which cracking does not occur is 12 mm is “6”. The ratio R / Da when the thickness Da is 4 mm and the radius of curvature R at which the crack does not occur is 12 mm is “3”.

  Further, as shown in Table 6, in sample 1, when the radius of curvature R is 15 mm and the thickness Da is 1 mm, 2 mm, and 4 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracking does not occur is 15 mm is “15”. The ratio R / Da when the thickness Da is 2 mm and the curvature radius R at which cracking does not occur is 15 mm is “7.5”. The ratio R / Da when the thickness Da is 4 mm and the curvature radius R at which cracking does not occur is 15 mm is “3.75”.

  Further, as shown in Table 6, in Sample 1, when the radius of curvature R is 20 mm and the thickness Da is 1 mm, 2 mm, 4 mm, and 8 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracking does not occur is 20 mm is “20”. The ratio R / Da when the thickness Da is 2 mm and the radius of curvature R at which cracking does not occur is 20 mm is “10”. The ratio R / Da when the thickness Da is 4 mm and the radius of curvature R at which cracking does not occur is 20 mm is “5”. The ratio R / Da when the thickness Da is 8 mm and the curvature radius R at which cracking does not occur is 20 mm is “2.5”.

  Thus, in Sample 1, when the radius of curvature at which cracking does not occur when the 90-degree bending test is performed and R is the thickness, the ratio R / Da is “6”, “3”, “9”, “4.5”, “12”, “6”, “3”, “15”, “7.5”, “3.75”, “20”, “10”, “5”, “2.5” " In the present embodiment, the minimum value of the plurality of ratios R / Da obtained is used as the evaluation value of the formability of the aluminum composite material 100. In sample 1, when the radius of curvature R is 20 mm and the thickness Da is 8 mm, the ratio R / Da shows the minimum value “2.5” (see the shaded portion in Table 6).

  For example, as shown in Table 5, in sample 4, when the radius of curvature R is 6 mm and the thickness Da is 1 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracking does not occur is 6 mm is “6”.

  Further, as shown in Table 5, in sample 4, when the radius of curvature R is 9 mm and the thickness Da is 1 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracks do not occur is 9 mm is “9”.

  Further, as shown in Table 5, in sample 4, when the radius of curvature R is 12 mm and the thickness Da is 1 mm and 2 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the radius of curvature R at which the crack does not occur is 12 mm is “12”. The ratio R / Da when the thickness Da is 2 mm and the radius of curvature R at which cracking does not occur is 12 mm is “6”.

  Further, as shown in Table 6, in sample 4, when the radius of curvature R is 15 mm and the thickness Da is 1 mm and 2 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracking does not occur is 15 mm is “15”. The ratio R / Da when the thickness Da is 2 mm and the curvature radius R at which cracking does not occur is 15 mm is “7.5”.

  Further, as shown in Table 6, in sample 4, when the radius of curvature R is 20 mm and the thickness Da is 1 mm and 2 mm, no crack occurs. The ratio R / Da when the thickness Da is 1 mm and the curvature radius R at which cracking does not occur is 20 mm is “20”. The ratio R / Da when the thickness Da is 2 mm and the radius of curvature R at which cracking does not occur is 20 mm is “10”.

  Thus, in Sample 4, when the radius of curvature at which cracking does not occur when the 90-degree bending test is performed and R is the thickness, the ratio R / Da is “6”, “9”, “12”, “6”, “15”, “7.5”, “20”, “10”. In the present embodiment, the minimum value of the plurality of ratios R / Da obtained is used as the evaluation value of the formability of the aluminum composite material 100. In sample 4, when the radius of curvature R is 6 mm and the thickness Da is 1 mm, the ratio R / Da shows the minimum value “6” (see the shaded portion in Table 5).

  The sample 1 and the sample 4 have been described above as examples. In this embodiment, the minimum value of the ratio R / Da is obtained for all samples (sample 1 to sample 18) (see the shaded portions in Tables 5 and 6). Table 4 shows the minimum value of the ratio R / Da of Sample 1 to Sample 18.

  In this embodiment, the minimum value of the ratio R / Da of sample 1 is “2.5”. The minimum value of the ratio R / Da of sample 2 is “2.25” (in Table 4, 2.25 is shown as an approximate number 2.3). The minimum value of the ratio R / Da of sample 3 is “3.75” (in Table 4, 3.75 is shown as an approximate number 3.8). The minimum value of the ratio R / Da of sample 4 is “6”. The minimum value of the ratio R / Da of the sample 14 is “2.5”. The minimum value of the ratio R / Da of sample 6 is “4.5”. The minimum value of the ratio R / Da of sample 7 is “6”. The minimum value of the ratio R / Da of sample 9 is “6”. The minimum value of the ratio R / Da of the sample 10 is “7.5”. The minimum value of the ratio R / Da of the sample 11 is at least “20”. The minimum value of the ratio R / Da of the sample 15 is “7.5”. The minimum value of the ratio R / Da of the sample 16 is “1.875” (in Table 4, 1.875 is shown as an approximate number 1.9). The minimum value of the ratio R / Da of sample 5 is “4.5”. The minimum value of the ratio R / Da of sample 8 is “7.5”. The minimum value of the ratio R / Da of the sample 12 is “15”. The minimum value of the ratio R / Da of the sample 17 is at least “20”. The minimum value of the ratio R / Da of the sample 18 is at least “20”. The minimum value of the ratio R / Da of the sample 13 is at least “20”.

  As shown in Sample 1 to Sample 4 and Sample 14 in Table 4, when the base material 3 contains gadolinium oxide particles in an amount of 6% by mass to 30% by mass, the elongation is about 8% or more (8.0 % And 20.8% or less), and when the radius of curvature at which 90-degree bending test does not cause cracking is R and the thickness is Da, the formability represented by the minimum value of the ratio R / Da is 2 It can be confirmed that the aluminum composite material 100 having a size of 3 or more and 6.0 or less can be manufactured.

  Further, as shown in Sample 6, Sample 7, Sample 9, Sample 10, and Sample 15 of Table 4, gadolinium oxide particles and boron carbide particles are dispersed in the base material 3, and 2 gadolinium oxide particles are present in the base material 3. In the case where 10% by mass or more and 10% by mass or less and boron carbide particles are contained by 10% by mass or more and 20% by mass or less, the elongation is about 6% or more (6.7% or more and 11.2% or less), Aluminum composite whose formability represented by the minimum value of the ratio R / Da is 4.5 or more and 7.5 or less, where R is the radius of curvature that does not cause cracking when 90-degree bending test is performed, and Da is the thickness It can be confirmed that the material 100 can be manufactured.

  As described above, according to this embodiment, since the gadolinium oxide particles are dispersed in the base material 3 of the aluminum powder, the aluminum composite material 100 having neutron absorption performance and good tensile properties is provided. The In addition, by dispersing both gadolinium oxide particles and boron carbide particles in the base material 3, an aluminum composite material having a good balance in performance such as neutron absorption performance, workability, and manufacturing cost is provided.

  The gadolinium oxide particles are cheaper than, for example, gadolinium, and are advantageous from the viewpoint of raw material costs. Further, according to the knowledge of the present inventors, when gadolinium oxide particles are added to aluminum powder in the existing casting process, the gadolinium oxide particles are not uniformly dispersed, and the quality of the manufactured article may be lowered. It has been found. In the present embodiment, aluminum powder and gadolinium oxide particles are mixed and gadolinium oxide particles are uniformly dispersed in the aluminum powder, and then the material to be rolled 18 is sandwiched between cases (metal plate). The aluminum composite material 100 having the base material 3 in which the gadolinium oxide particles are uniformly dispersed in the aluminum powder can be produced by producing and rolling without passing through a sintering step or the like. Thus, by using the manufacturing method according to the present embodiment, the base material 3 in which gadolinium oxide particles having excellent neutron absorption performance at low cost are uniformly dispersed in the aluminum powder can be manufactured and manufactured. This contributes to improving the quality of the aluminum composite material 100. Moreover, the aluminum composite material 100 excellent in workability can be provided by the gadolinium oxide particles.

  In this embodiment, the to-be-rolled body 18 is formed by filling the case 10 with the mixed material M and sealing the case 10 in a state where the filling density of the mixed material M is increased by tapping. Moreover, the to-be-rolled body 18 has a structure in which the mixed material M as a powder is sandwiched between the upper case 14 and the lower case 12. As a result, the aluminum composite material 100 as the clad material can be manufactured in a state where the high packing density of the mixed material M is maintained by preheating and rolling the workpiece 18.

  In the present embodiment, the upper surface of the base material 3 (mixed material M) of the clad structure and the metal plate 1 (upper case 14) are in close contact, and the lower surface of the base material 3 (mixed material M) and the metal plate 2 ( Since the lower case 12) is in close contact with each other, the layers adjacent to each other are firmly bonded. As a result, the mechanical strength of the aluminum composite material 100 increases dramatically. Moreover, in this embodiment, since the surface of the aluminum composite material 100 is formed of the metal plate 1 and the metal plate 2 and there is no particle, for example, the surface is less likely to be destroyed than an existing sintered body. A rolled material can be obtained.

  That is, when a metal powder containing a large amount of ceramic particles is sintered to form a sintered body as in the prior art, and the sintered body is plastically processed, the ceramic particles on the surface become the starting point of destruction, There is a strong tendency to crack in plastic working materials. There is also a problem that the extrusion die, the rolling roller, the forging die and the like are worn. However, in this embodiment, since the surface of the aluminum composite material 100 is formed of the metal plate 1 and the metal plate 2 and no particles are present, for example, compared to an existing sintered body, the surface has a fracture base. And there are no ceramic particles that wear the dies. Thus, the effect that a favorable rolling work material can be obtained can be acquired.

  In the present embodiment, the upper surface (upper case 14) and the lower surface (lower case 12) of the hollow case 10 function as the upper and lower metal plates 1 and 2 when forming the clad material. The structure as the clad material is completed in a state where the material M is filled in the case 10, and the manufacturing process is simplified. Furthermore, since the mixed material M in the hollow case 10 is used in the rolling process in the form of powder, the bulk density maintained in a state where the mixed material M is filled in the case 10 is the maximum. It can be done up to about 65%.

  In the above, various useful examples of the present invention have been shown and described. It goes without saying that the present invention is not limited to the above-described various embodiments and modifications, and can be variously modified without departing from the gist of the present invention and the contents described in the appended claims. No.

DESCRIPTION OF SYMBOLS 1 Metal plate 2 Metal plate 3 Base material 10 Case 12 Lower case 14 Upper case 18 Rolled object 100 Aluminum composite material

Claims (9)

A first metal plate;
A second metal plate;
A base material disposed between the first metal plate and the second metal plate, formed of aluminum powder, in which gadolinium oxide particles and boron carbide particles are dispersed;
The aluminum composite material in which the content of the gadolinium oxide particles in the base material is 2% by mass or more and 10% by mass or less, and the content of the boron carbide particles is 10% by mass or more and 20% by mass or less. A first metal plate;
A second metal plate;
A base material disposed between the first metal plate and the second metal plate, formed of aluminum powder, in which gadolinium oxide particles and boron carbide particles are dispersed;
The content of the gadolinium oxide particles in the base material is 2% by mass or more and 20% by mass or less, and the content of the boron carbide particles is 10% by mass or more and 20% by mass or less.
An aluminum composite material having an elongation of 2% or more. A first metal plate;
A second metal plate;
A base material disposed between the first metal plate and the second metal plate, formed of aluminum powder, in which gadolinium oxide particles and boron carbide particles are dispersed;
The content of the gadolinium oxide particles in the base material is 2% by mass or more and 10 % by mass or less, and the content of the boron carbide particles is 10% by mass or more and 20% by mass or less.
The elongation is 6% or more,
The curvature radius R is 6 mm or more and 15 mm or less, the thickness Da is 1 mm or more and 8 mm or less, and the ratio R / Da is expressed as R when the radius of curvature is 90 ° and the thickness is Da. An aluminum composite material having a formability of 4.5 or more and 7.5 or less.   The aluminum composite material according to any one of claims 1 to 3, wherein at least one of the first metal plate and the second metal plate is made of aluminum or stainless steel. A first metal plate;
A second metal plate;
A base material disposed between the first metal plate and the second metal plate, formed of aluminum powder and having gadolinium oxide particles dispersed therein,
The content of the gadolinium oxide particles in the base material is 6% by mass or more and 30% by mass or less,
Elongation rate is 8% or more,
The curvature radius R is 6 mm or more and 15 mm or less, the thickness Da is 1 mm or more and 8 mm or less, and the ratio R / Da is expressed as R when the radius of curvature is 90 ° and the thickness is Da. The moldability is 2.3 or more and 6.0 or less,
At least one of the first metal plate and the second metal plate is an aluminum composite material made of aluminum or stainless steel. Mixing aluminum powder and gadolinium oxide particles;
A step of filling a case with a mixed material generated by the mixing to form a rolled body; and
Heating the rolled body;
Rolling the heated rolled material to produce an aluminum composite; and
Including
The mixing step further includes mixing boron carbide particles;
In the aluminum composite material, the mixing is performed such that the gadolinium oxide particles are contained in an amount of 2% by mass or more and 20% by mass or less and the boron carbide particles are contained in an amount of 10% by mass or more and 20% by mass or less. Production method. The case includes a first case and a second case,
The step of forming the object to be rolled includes filling the concave portion of the first case with the mixed material and covering the opening of the concave portion filled with the mixed material with the second case. Item 7. A method for producing an aluminum composite material according to Item 6.   The method for manufacturing an aluminum composite material according to claim 7, wherein tapping the first case in filling the mixed material into the first case.   The first case is filled with the mixed material such that the upper surface of the mixed material filled in the concave portion of the first case and the upper surface of the first case around the concave portion are arranged in the same plane. A method for producing an aluminum composite material according to claim 7 or claim 8.